Brent Colefax, played by Texas Watterston, made his first appearance on 13 July 2020. Watterston's casting was confirmed by his acting agency. Watterston was originally contracted for eight episodes, but ended up filming around 50 episodes after being brought back by producers. Matt Wilson, who plays
Aaron Brennan, hoped that Watterston and Justin Ezra, who plays Brent's half-brother
Emmett Donaldson, would become series regulars, calling them both "great performers". In October 2021, Watterston told
Digital Spy's Daniel Kilkelly that he was happy playing a guest role, as it allowed him to pursue other jobs. He explained, "I think at the moment Brent's a perfect guest role character. He comes in and out when he wants and he makes his impact on screen." Watterston said he would consider joining the serial on a permanent basis if he were asked, as he was interested in what the writers would do with Brent. Writers later established a romantic relationship between Brent and Harlow. Donovan admitted to being surprised when she learned the characters would kiss. She worked with the writers to make sure the story was told "appropriately and truthfully". She said: "I think there was a genuine want for change from Brent and it was shown through his actions. For Harlow, that was promising and could also see that he wanted to do good and move forward. She kisses him impulsively and she suddenly freaks that she isn't ready and then pulls back. She questions herself, is this really what she wants?" Watterston told Alice Penwill of
Inside Soap that Brent is so surprised by Harlow's personality change that their relationship "begins to spiral". He described them as being on "different levels", and when Harlow makes it clear she is not happy with Brent, he "keeps his cool", which Watterston thought would surprise viewers. At the end of his guest stint, Watterston stated "Even though my character can only go so far, I still feel as though there's a storyline for Brent." He added that he would return in the future if he were asked. Brent is Emmett Donaldson's older half-brother, who comes to Erinsborough to see him. He meets Emmett's foster parents
David Tanaka (
Takaya Honda) and Aaron Brennan (Wilson), and tells them that as soon as he turns 18 he wants Emmett to live with him. David and Aaron question whether he is ready for that kind of responsibility. Brent encourages Emmett to sneak out to the city with him, angering Aaron who went out to get them dinner. He plans to take Brent back to his care home, but Brent refuses to go back, so Aaron says he can stay the night. Brent flees when David and Aaron tell him that Emmett will unlikely be allowed to live with him. Aaron finds him at the
Lassiter's complex and Brent says that he and David will let Emmett down, just like the other foster carers, but Aaron assures him that it will not happen. Brent convinces Emmett to climb onto the roof of the house, but when Aaron catches them coming down, Emmett falls and suffers a spinal injury. At
Erinsborough Hospital, David's father
Paul Robinson (
Stefan Dennis) blames Brent for Emmett's accident, prompting Harlow Robinson to apologise for his outburst. She tells Brent that they are just worried about Emmett. David and Aaron invite Brent to stay with them, but are frustrated when he does not clean up after himself. Brent visits Harlow and asks her out on a date, but when she turns him down, he gets aggressive and threatens her. David and Aaron confront him and Brent starts throwing items around the kitchen, before he elbows Aaron in the face. Brent has to return to the care home, and he is packing up his belongings when his mother
Jenna Donaldson (
Anna Lise Phillips) comes to see him and Emmett. Aaron tells Brent that he can visit any time, while Brent promises to call Emmett every day. He also tells his mother that he will think about her offer to live with her when he turns 18. Brent returns to Erinsborough the following year and hides out in Aaron and David's garden bar, The Dug Out. The couple find him sleeping rough and offer him a place to stay, much to Paul's annoyance. After some reluctance, Brent agrees to return to school to complete Year 12. On his first day, he clashes with Hendrix Grayson, Harlow's ex-boyfriend who is also repeating and the two begin a feud. Hendrix becomes increasingly annoyed with Brent spending time with Harlow and the two fight. After Brent breaks Hendrix's laptop,
Susan Kennedy (
Jackie Woodburne) loans Hendrix hers. Hendrix, then finds Brent's confidential school records and accidentally uploads them to the school server. Brent is left devastated after the files are leaked and Harlow comforts him.
Jane Harris (
Annie Jones) suggests a Year 13 initiative for the boys, geared towards independent study. Brent and Hendrix continue to argue during a food tech class where Brent deliberately ruins Hendrix's soufflé and winds him up into throwing the bowl at him, which he ducks. Jane enters and slips on the mess and almost injures herself. In spite of this, the initiative continues with
Curtis Perkins (Nathan Borg) overseeing it. Harlow begins tutoring Hendrix and there is an attraction between the two. Brent gives Harlow a gift and she kisses him. Harlow initially dismisses it, but Brent's feelings grow. He then gives Harlow a USB containing his personal files in order to be honest and open with her. After the site of Brent's work project at Eden University is vandalised, Harlow admits to Paul that she is seeing Brent, which angers Paul. Brent receives a threatening text message from
Holden Brice (Toby Derrick) and the same day Number 32 is ransacked, leaving
Nicolette Stone (Charlotte Chimes) shaken. He then receives a skull ring in an envelope. When Brent and Emmett's aunt
Linda Donaldson (Amelia Best), wants to take Emmett to
New Zealand with her, he appeals to Aaron and David to help Emmett. Nicolette agrees to move out in order to help Emmett's chances as she has a criminal record. At Dinner, Brent stands his ground against Paul telling him that he and Harlow will be a couple whether he likes it or not. When Brent realises he has lost the ring under the couch at Number 22, he returns to look for it and recovers it only to be met by Holden. It is revealed that Holden is responsible for attacking Roxy Willis and vandalising the mural, as well as the break-in at Number 32. Holden leans on Brent to hide a stolen bike he is selling. After a robbery at
The Hive, Brent and Holden are both arrested and receive criminal charges before they are sent into remand. Paul recruits
Toadie Rebecchi (
Ryan Moloney) as Brent's lawyer. Holden lies to the authorities about Brent's involvement in the gang's crimes and more charges are brought against Brent. Curtis visits Brent with Toadie and suggests that Brent should join the
Australian Defence Force instead of going to prison. Brent agrees that he would rather do that and Toadie makes it possible. Before Brent says goodbye, he announces that he will be based in
New South Wales. He and Harlow agree to a long distance relationship. Brent then says goodbye to Aaron, David, Jane, Terese and Paul and is escorted out by Harlow. He later agrees to Harlow's plan for
Jesse Porter (Cameron Robbie) to pose as her boyfriend to avoid Paul's interference. A few months later, Brent returns to Erinsborough and greets Harlow in
Harold's Café. He discovers that Paul paid Holden to give false a testimony against him. When Harlow expresses her support for Paul, Brent ends their relationship. He tells Harlow that she is a different person, and he leaves for New Zealand to live with his brother and mother. ==Nicolette Stone==